Clapton mid boost into pedal format?

[drummonkey4jc]

Hello folks who are smarter than I...
I am in over my head trying to put the Eric Clapton mid boost in a pedal format. Basically the thing was designed to be integrated into the guitar's volume and tone knobs, and has a separate mid boost control. What I am trying to get is a pedal with a switch and one mid boost knob. I have a bunch of diagrams and schematics that I am trying to combine to make it work, and I'm getting confused. Here are the things I've been looking at. Any help would be greatly appreciated. I think I can bypass the volume pot with a similar valued resistor, but after that I'm more or less clueless. Thanks!

http://tagboardeffects.blogspot.com/2014/02/fender-eric-clapton-25db-mid-boost.html
http://www.generalguitargadgets.com/diagrams/switch_lo_3pdt_ig_battery.gif
http://www.guitarelectronics.com/product/WDUSSS5L1203/WDU-SSS5L12-03.html
http://i197.photobucket.com/albums/aa211/bajaman002/FenderEricClaptonActiveElectronics.jpg

[GibsonGM]

Hi Monkey, welcome to the forum!  Have you built stuff before? It would be helpful to know a bit about your background...you seem to know at least a bit, anyway.   Knowing what/if you've built will help us figure out what way you should go with this. 

I've looked at the midboost before, and choose instead to play with Craig Anderton's Frequency Booster (use the "search" on here, you'll find the schem/links/discussions).  Works VERY well for what I do, and it is VERY mod-able.   Already set up as a pedal.

BUT - yes, you COULD build the EC midboost into a pedal, pretty easily, I bet.   IF you keep the guitar tone stuff separate, of course (TBX and all that - separate job, IMO).    I'd build it onto a pedal-sized PCB (perf, is what I use), WITH the volume AND mid controls.      Tune it in with your rig, measure the vol. pot resistances and replace the pot with 2 fixed resistances that set the vol. level you like.    Or just have a Vol and Mid on the pedal itself, even better!!

This guy will easily stand alone.  After all, if you had room, any pedal could be put IN the guitar, if you wanted to!  All that's different is the switching.    BTW, a quick net search says that 2N3904 / BC547 / PN2222 / 2N4401 are good substitutes for the 6429 called for in the circuit, and those are everywhere.

Any more specific questions?

[drummonkey4jc]

Thanks for the info. This will be my first pedal build, soooooo super noob. I pulled the circuit out of a guitar for want of switchability, so I have the built circuit already. I am just looking for guidance on how to wire it all up, since there are multiple ins and outs and weird connections between pots and such.
From what I'm gathering, it looks like having a volume pot will be helpful to dial in the pedal, so I think I'll leave that in. That simplifies things a bit, but I still have a few questions.

-I will need to add a switch/LED indicator, how would that affect the wiring? (I've checked this out :http://www.generalguitargadgets.com/diagrams/switch_lo_3pdt_ig_battery.gif, but it doesn't totally match up with the board I have)
-I'd also like to run it off wall power as opposed to battery. What changes (other than the connector) will be needed?
-Also (forgive my noob-ishness) where would I solder the grounds? to the volume pot like in guitars?
-And in the clapton wiring schematic, it uses a TRS connector for output (presumably to engage/disengage the battery), would that still be needed? Or should that be on the Input side, or both?

Lots of questions. Sorry! and thanks!!

[PRR]

> This will be my first pedal build

This is a *very* tricky build. LOTS of parts. (Almost looks like the designer got paid by the part.)

Try something simpler first, just to get some chops.

[Buzz]

Can you post a photo of the board you have?

Apart from the pot wiring you should have four wires left?

In / out / ground / +9v. If you can tell which is which the rest is pretty easy...

[Buzz]

Here's the GGG stompswitch wiring with a power jack added.





Should be OK to connect some grounds to the output jack. Just like in a guitar... make sure they all connect to each other somewhere.

[drummonkey4jc]

Here's a pic of the board:



and here's a diagram I came up with after hours of staring and drooling and combining of schematics:



look about right?

Also, would it be beneficial to swap the 50k volume pot with a 250k? I know in guitars that affects treble, but is that doable, or desirable? Or should I keep with the schematic's specifications?

Thanks for your guidance

[Buzz]

Looks good to me. I would say keep the 50k. It's an integral part of the circuit.

[pinkjimiphoton]

> This will be my first pedal build

This is a *very* tricky build. LOTS of parts. (Almost looks like the designer got paid by the part.)

Try something simpler first, just to get some chops.

+ like, 1,000!!!

[Buzz]

It shouldn't be too tricky.

He already has the board from a known working source.

He has labelled the function of the wires on taking it out.

And worked out how to adapt that into a stompbox.


Before the mass information available on the internet I managed to do the opposite, and stick a PCB from a pedal into a guitar. It worked.

Drum monkey is already miles ahead of where I was then. He'll get it done.

[drummonkey4jc]

I ordered the parts I need, and will put it together next week and let you know how it goes. I'm looking forward to having the switchable pedal version of this circuit. I really liked its sound, hopefully it's what I remember.

Thanks again! 

[Renegadrian]

built this ckt using THIS layout from tagboardeffects - I guess the mid boost part is not working, the more the knob is turned cw the more silence I get instead of mid boost, til I get complete silence at max position.
using all stock parts as per the layout but a 2n3906 in q4.
You guys can suggest me where I failed?! thx

[theear]

I did like this diagram But my pedal wont work?
Anyone ekar tried to build with this diagram?

Looks good to me. I would say keep the 50k. It's an integral part of the circuit.